Drill-chuck.



-wif'n comm P. E. BCORSBLSKI..

DRILL CHUCK.

APPLIGATION FILED MAY 1s, 1914.

,181,990. Patented Mar. 16, ma.

2 SHBETS*SHEET l.

fri' l www@ BE. BOGORSELSKI.

DRILL CHUCK.

APPLICATION FILED MAY 16, 1914.

1,131,990, Patented Mar. 16, 19M).

2 SHEETS-SHEET 2.

FRANK E. BOGORSELSKE, @E ISECHMGND, V'JEGIBHA.

Specification of Letters Patent.

canon.

Patented Maro i6, tm

Application filed may 18, 19M. Serial No. $339,061.

To all whom it may concern.

Be it known that l, FRANK` E. Booonsnr.- snr, a citizen of the'United States, and residing at Richmond, in thecounty oit Henrico and State of Virginia, have invented' certain new and useful improvementsin Drill-Chucks, of which the following is a specification.

This invention relates'to drill-chucks, and

its primary object is to provide a chuck or bit-holder so constructed as to engage a grooved drill-bit at diametrically-oppcsite points within its spiral groove.

A further object of the invention is to provide a bit-holder with oppositely-disposed clamping-arms provided with ngers adapted to engage a drill-bit at diametrically-opposite points, said fingers extending into the grooves of the bit and to clamp the bit without tapering the drill-head and without requiring the tapered sleeve usually employed -to secure the shank of a twistdrill bit to its head. i

A still further object of the invention is, to provide a bit-holder or chuck so yconstructed as to permit a twist-drill bit to be inserted into or withdrawn from, its holder or chuck by a rotary movement of the bit, thus especially Aadapting the improved holder foruse in connection with a reversible shankless bit.

With this brief outline of the main objects of the present invention, the same will now be specically described in connection with the accompanying drawing which constitutes a part ofthis specification; and its elements of novelty and distinguishin features over the prior artwillbe set fort and delined in the appended claim.,`

In the drawing: Figure-1 is a central longitudinal section of one embodiment of the invention, the drill bit being illustrated by dotted lines. Fig. 2 is an end elevation of the bit-holder vand bit, the latter being shown in transverse section. Fig. 3 is a section taken on the line 3--3 of Fig. l, illustrating one means for pivotally securing the fingers of the bit-holder to the drill head, Fig. 4 is an end elevation similar to Fig.2 showing bit-engaging lingers 4 of slightly modified form. Fig. 5 is a central longitudinal section of a modified construction of chuck or drill-holder embodying the invention. Fig. 6 is an end elevation of the' same, and, Fig. 7 is an elevation of the at .support for the armsI may y'ring' shown in Figs. 5 and 6 detached from the chuck.

rllhe reference numeral 10 designates the hollow cylindrical head of the bit-holder 0r chuck having external threads ll at one end for the engagement thereon of a clamping sleeve l2 formed with internal screw threads 13. ylihe head 10 is channeled or recessed at diametrically-opposite points to provide a pair of parallel shoulders 14e at each side of the head between which are pivotally secured, two clamping arms 15, the tree endsof which are each formed-with a rounded nger 16, said ngers being transverselyalined and projecting toward each other to project into the grooves 17 of' a shankless reversible bit 18 and tightly engage the body of the bit within the grooves, at diametrically-opposite points as clearly -shown in Figs. 1, 2, and d.

4each having a perforation registeringwith the openings inthe shoulders. This pivotal be al screw as shown inxFig. 3, or any equivalent securing device might be employed. The outer sides 26 of the arms-15 are referably slightly. inclined to co-act with the rounded edge'21 of an annular flange 22 projecting inward from one end of the sleeve 12, the opposite end of which is milled or corrugated as at 23 to facilitate the turning of the sleeve to tightly clamp the fingers 16 upon the bit, or to loosen the fin ers to ermit of the ea withdrawal of the it. T 1e drill head 10 1s provided with an suitable shank or s indle projection 24 at its unthreaded endor attachment to anysuitable rotating means, not shown; and is also provided in addition to a bit-'receiving bore 25, witha cylindrical chamber 26 communicating with and consti tuting a diametrically-reduced extension ot the bore 25, and forming an annular shoulf der 27 within the drill head. The utility and operation of the improved bit-holder constructed as above described, will be readily understood by those skilled in the art lto which the invention relates. When the sleeve 12 is turned to loosen the clamping arms suliiciently, one end of a shankless reversible bit, pointed at both lends, vis insertedbetween the ngers ion clamp the n'gers 16 .on opposite sides of l the bit within its grooves at diametrically opposite points, thus firmly holdingthe bit within the drill head to rotate therewith.

In the form of the device shown in Fig. 4, the bit 18l is shown on a slightly largerl scale, the grooves 17 are of different and Hatter contour than the corresponding parts in Fig. 2; and the ngers 16a are flattened more than the finger 16 of Fig. 2. Otherwise this modified construction is identical with that shown in 'the other figures of the drawing.

Referring now to Figs. 5, 6, and 7 of the drawing, the numeral 10 designates the chuck-head, and 15a `the clamping arms thereof. pivotally-secured within the head as already described in connection with Figs. 1 to 4. The sleeve 12a instead of being provided with the interior end ange 22 as in Fig. 1, is formed with an annular shoulder against which fits a clamping ring28 rounded on itsA inner surface as at 30 to bear upon the free ends of the arms 15, and formed with diametrically opposite lugs 31 fitting in slots of the head 10.` An externally-threaded flat ring 29 engages internal threads of the sleeve 12El to hold the clampin ring in position.

It wil be noted that the improved bitholder is especially well adapted to receive a reversible, shanlrless bit but contemplates and includes broadly, a bit-holder having A reversible bit formed without a shank,

and especially designed for use with the present invention, constitutes the subjectmatter of another application filed by me, May 16, 1914, Serial No. 839062.

I would have. it understood that the invention is not restricted to the details of construction except as hereinafter claimed, but includesy all such modifications and variations in structural details as may fall within the scope and terms of the claim.

What I claim as new 1s:-

A drill chuck embodying an externally threaded head provided at its outer end with ttvo pairs of transversely alined spaced shoulders, a pair of jaws having their inner ends pivoted between the shoulders, and their outer ends terminating in inward projecting oppositely alined terminally rounded fingers, and a sleeve threaded on the head and furnished at'its outer end with an inward projecting transversely rounded annular flange to engage the jaws.

In testimony whereof I affix my signature in presence of two witnesses. g i

. FRANK E. BOCORSELSKI.

Witnesses:

RALPH S. COOPER, Moms W. CoRBY. 

